After sell service:1.1 years warranty,by replace/repair/free spare parts for bulk order.Within the first year, if you need any spare parts for replacement, we can provide to you without paid. And we will offer lifelong technical support and service.2. Considering the expensive shipping cost for you,broken rectifier is no need to send back to China, just let us know the problem through a video or a picture, then,we will send the replacement to you immediately&period. After sell service:1.1 years warranty,by replace/repair/free spare parts for bulk order.Within the first year, if you need any spare parts for replacement, we can provide to you without paid. And we will offer lifelong technical support and service.2. Considering the expensive shipping cost for you,broken rectifier is no need to send back to China, just let us know the problem through a video or a picture, then,we will send the replacement to you immediately&period.
I am using Motorola GM 300 series radios. Reply Delete. My name is Kevin and I am attempting to set up a dmr repeater using your mmdvm repeater kit board and a kenwood TKR-850. I am having problems with the transmit drive level. Even with the TX pot full open and levels set to%100 in mmdvmcal, I cannot get enough.
GM300 Information PageMotorola GM300Information PageBy Robert W. Meister WA1MIKThe GM300 was Motorola's next step in the MaxTrac / Radius mobile product lines.The schematics are remarkably similar. You can even interchange some boards betweenthe GM300 and MaxTrac radios. Like the MaxTrac, the GM300 line has been discontinuedby the manufacturer. Throughout this article, reference to MaxTrac radios impliesRadius radios as well.Naturally, you need different programming software (RSS), but if you've everprogrammed a MaxTrac, you'll be right at home with the GM300. The radios operate thesame, too. See below for more info on the RSS and programming.GM300 mobile radios cover the VHF (136-174 MHz in two ranges) and UHF (403-520MHz in four ranges) bands, with 8 or 16 channels, 12.5 or 20/25/30 kHz channelspacing, and 10, 25, and 35-45 watt power levels.
They use the same accessories(loudspeakers, microphones, accessory plugs, power cords, mounting brackets, etc.)as the MaxTracs.The M120 radio is just about the same as a GM300 but has 'less features' - thiswould be the 2-channel version, equivalent to a MaxTrac 50. There is also an M10single-channel radio, and an M130 2-channel radio that is an M120 with the GM300'ssignaling capabilities.The 16ch GM300 radio uses the expanded logic board with firmware in an EPROMthat gives you the ability to program several of the accessory jack pins and alsogives you several signaling systems, such as MDC1200. The 8ch GM300 and theM-series all use the masked logic board that has no programmable pins. The maskedlogic board also has limited code plug space, hence fewer channels and lesscapabilities.Here's a front view photo of a 16-channel MaxTrac, a 16-channel GM300, and a2-channel MaxTrac:GM300 Model Numbers:The first six characters are pretty much standard Motorola convention.
The IFfrequency is usually 45.1 MHz but if you have multiple radios near each other, thiscan cause interference, so you can optionally order the radio with an alternate IFfrequency.MountPower WattsBand MHzSeriesI.F. MHzM: dash0: 1-103: 136-174GM:?C: 45.13: 10-254: 403-520XQ:?R: 45.34: 25-45XV:?The XV-series seems to all be 1 channel radios. The XQ-series seems to be all 2channel radios. The GM-series can be 2, 8, or 16 channel radios. The XV and XQ maybe used by the M10, M120, and M130 radios.The second six characters provide a lot of useful information about the capabilitiesof the radio and the boards contained within it.Spacing kHz# Ch.Logic BoardRange MHzRev.0: 12.50: 8C: Expanded1: 136-162A2: 20/25/309: 16D: Masked1: 403-4302: 146-1743: 438-4704: 465-4905: 490-520A typical model number would be M44GMC09C3A. This is a 40 watt, UHF radio, 45.1MHz IF, narrow spacing (12.5 kHz), 16 channels, expanded logic board, 438-470 MHzband.It is rare that the model number includes the specific frequency range the radiois capable of handling (10th character).
You don't get that lucky with MaxTracs,Spectras, etc. I wish all the model numbering was so useful. It is NOTpractical to change the frequency range for which the radio was manufactured.
The RFboard and PA assembly are frequency-dependent; the logic board and front panel arenot. As the model number tells you which range the radio is, if you end up with thewrong one (assuming the radio hasn't been thrown together out of spare parts or hadmodules swapped) it's your own fault for not doing your homework.The expanded logic board has its firmware contained in a socketed EPROM, whichcan be replaced. The masked logic board has its firmware permanently stored in thesoldered-in microprocessor IC.
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People have apparently modified the RSS to get 16channels from masked logic board radios and 40 channels from expanded logic boardradios.It would appear that GM300s are not capable of any form of trunking operation.However they can do G-Star signaling for use with GE radio systems.There are other models, such as M10, that are often called GM300. This articleis specifically oriented towards the radios with 'GMC' in the model number.Specifications:Click on the image to enlarge it.Note that a revision to the service manual shows two VHF ranges: 136-162 MHz and146-174 MHz.